Underreamer



Jul 28, 1931.

F. SWAN 1,815,937

UNDERREAMER Filed Jan. 8. 1929 IN VE N T OR DZ ATTORNEY 3 Sheets-Sheet lJuly 28, 1931. F. SWA1V 1,815,937

- 7 I I UNDERREAMER I v Filed Jan. 8, 1929 {sweets-sheet 2 v INVENTOR YF g 511. 10 .42 1 2111 A TTOR/VEY July 28, 1931. F, SWAN 1,815,937

UNDERREAMER 3 Sheets-Sheet 3 Filed Jan. a, 1929 mug/A M j;

15 end of Whic Patented July 28 1931 V L FRED swim, oewxcrirm, Kansas,'ASSIGNQR arc-THE BRIDGE-roar MACHI E corn PANY, 61 wIoHITA, :KA-NsAs,VA CORPQ-BATION OFVDELAVWARE" i UNIDERREAMER f 1 ap ease filed was s, 192e.f se;ia1no. 331,140.

This inventionrelates to underreamers and the 'primary 'ob 'ect thereofs to provide an efiioient simple construction of underreamer in vvhic'hexpandingiand contracting cutters 5 can he ex editiously applied to thestock or head and easilyreinoved, when it is necessary tore pair or"redressthem.,, The cutters are Tadaptedtorideupon an expander d e to aspring responsive actuating rod which is'con nected to'the reins ofthecutters hya crosshar ot novel-construction V, The crosssbar isanimportan't feature of the invention because it, permits. convenientremoval of the cutters vvhenever it is" necessary to repair or redress tem a itfllso p-efmitsithereins torbe 0P9? gme q i t d with the a t nged. iWheH,filmyihit h ii m i he head v o y I 711311 arms or'rein's,1 'a1 1 1 at l or stock;

"The e bf; the "inven ion will he rap- 1 -g kp ren y" r ere e I th T QIIed i P-o ti qn inj connection withfthe accompanying adrawmgsin whichiF'g: 1' s: an ele at o View 31nd, finder? f' inventioni". 5 A o e,

2 is, a sectional viewthroughparto'f a Fig.

Welt casing showing the head or; stock, the

,-o actuating rod, the c'iitters and egrpander, parts being inelevati'omparts. insectli'on and certain 3 ofithe parts-being brokenaWay'to better illuswe certain other parts' the cutters being shown asin contracted positions.

, .i Figb -xifs a likeview showing the critters .linexpandedpesitions.'-

1 .35 1F'i'g Aisa} detailed perspectivevievv'of one cithhritters. I o e;;-Ei'g '5 isxan endviewot thefnnderreamer.

1g. 6is anenla-rged vi wer the cross-bar.

,Figfl is ahottom vievviof the cross-har V '40 fFiglS isanenlargedcI'QssQseCtiOIIaI vievv I 1 Reterringnovv tothe'drawingsbyjnomera Figf 10 is a perspective view o'f of referenceglld'esignatesfthe; oil wy'ell' casing, Qisthe head r-stockQprovidedfvvthja shank o ifhavifig s nag harrelorr'ecess 4 :the lmyer e m-em 1reameroonstrutedainaccordance with my fljhe ends er the 'crosspar arebeveled 29 and. to prcvict phcts fie assist I a seat forone end ofthe/coil spring 6,the

opposite end bearing against the enlargement or head 7 of the cutteractuated rod 8 also in the recess 4:. The lower end of the rod 8projectsbelow the seat and hasa slotted head or loop 9 to receivethecross-bar 10. 'The cross-bar passes through a .slot in, the head and itcarries the reins of the cutters 11 and 12 as will be presentlyexplained. Thehead 3 carries a depending l expander 01' tongue 13 oflesswidth than that of the headsothat shoulders 14 and 15 are formed toact as stops to limit the slidingmovernent of the cutters [in onedirection. Each cutter consists of a cutting headl having 'a curved face15' to cut away the earth'belovv the bottom of the casmgorfpipe 1 andeach cutter is'provideid their upper ends with slots 18 and l9'throughwhich the cross-bar is adapted to pass. The

standing projection,22 in spaced rel ation wlththe projections 20. and21. fOnonel face of the rectangular [block or member 10 are tvvo groovesor kerfs 23 and 24 to receivethe reins of one of the cutters forexample; the

cutter; 11 and on the opposite face/ofthe' rectangular bar or block aresimilar grooves or ker'fs 25 and 26 to receive the'reins-of the othercutter; for example, the cutter 19.

These kerfs increase in depth fromthe top to. the bottom, from zerothickness toan er fpreciable depth-,sothat the edges oi the {reins willbe retained in the grooves or kerfs d1iring the'expanding operation ofthe cutters as'well as when expanded. The cutters areinterchangeablesince they'are duplicates one of the other and theirendsoverlaplvilfi shown in Figure 5., The Widths. of the ker fsgjorgrooves are substantially Y equal to? the thicknesses of thereins butthe edgesot the keris ,or grooves are slightly beveled as indicated at2'1 to provide a relief so that thereinsvvill Hand in the slot28 of; theheaded portions;

as a we easily moveiinto the kerfs or grooves whern ,the'crossebar'isinsertedin the slots 18 and v projections and ing the cross-bar'into theslots. The inner faces of the projections 20'and 21 are also slightlybeveled as indicated at 31 and 32 to guide the reins into the spacebetween the 21 and the intermediate projection22. V 1 V 1 It will beObserved that the actuating rod 8 'is' provided with an intermediateenlarged portion33'provided with ars'lot 34. This slot is adapted toreceive a dent ordrift key 35 (see Fig. 10, Sheet 1) when the cuttersarein collapsed position as shown in Figure 2 so that the cutters can beheld against ex- Y pandingwhen they are being set in'the casing.Ashearable pin 36 can pass through openings 37 and 38in the cutters 11and 12 tohold'them collapsed prior tobelng set and in orderto collapsethem, they can be 7 held between the hook-shaped members 39 and 40 fasttothe eye 41 on the floor. The head isprovided. with relief ports44 and45 (see Figure. 3). .I r vWhen it is desired to connect the cutters tothe head, the actuating rod will be pulled V r the lower end ofthecasing causing the spring down and held against the expansive force,of the spring by the drift key 35. Then, the 1 reins ofthe cutters canbe caused to straddle the head and the'cro-ss bar 10,insertedthr0ugh the-slots-18, 19 and 28 'so that the reins w1ll drop inthe-kerfs'providedto receive them.

The cutters can be retracted and held bythe drift key 35 so that the pin36 can be inserted. ,Then,,the drift key 35 canbe removed and theunderreamer against the bottom of the well will breakthe pin 36,allowing the spring 4 'to impart an upward movement to the actuating rodcausing the cutters to ride onlthe expandertongue 13 and move Intoexpanded and cutting position shown 1n Flgure 3. After the cuttingoperation has been.

completed, an upward pull on the head will cause thefshoulder's 42 and43 to contact with to be contracted, permitting the expanded tongueupward relative to the cutters and thereby permit the cutters to retractwithin the casing soi that the underreamer can be removed.

In Figure 5 I have shown that the reins of the cutters alternatelyoverlap. Thisenables themanufacturer to'standardize the cutters so'thatthey are interchangeable.

, This is anlimp'ortant feature as it reduces the number'of cuttersrequired around an It 'willflbe apparent that the device is simple inconstruction, ruggedfand that the cut ters'can be easily assembled anddisassernbled with respect to the head or stock.

' It will be apparent from the drawings that the slot 28 is longer thanthe widthof the crossbar 10 so that there can bevenough play of thecross-bar'inthe slot 28 ,to take theten- 'sion off thesprin'g' i whenthe shoulders 42 and 43 abut against the stop shoulders ,14 and 15.

What I claim and ters Patent is v V '1. An' underreamer comprising aslotted head, cutters having slotted reins and acrossbar insertablethrough the slot in the head desire to secure by Letand through theslotted reins, the cross-bar 3. ,An underreamer comprising a. slottedhead, cutters having slotted reinsand a crossbar insertable through theslotin the'head and through the slotted reins, the cross-bar having sideand edge grooves to receive the edges of the slots in the reins, thesidegrooves being of progressively increasing depths across the bar. 1 v u4. An underreamer comprising a slotted head, anexpander tongue dependingfrom the head, cutters having slotted reins straddling the tongue and across-bar for'connecting' the reins to the head insertable' through theseveral slots and provided with staggered groovedportions on its sides,the widths of the grooves-being substantially equal to the thicknessesof thereins. .I v

5., An underreamer comprising a slotted head, an expandertonguedepending from the head, cutters having slotted reins straddling thetongue and a cross-bar forconnecting the reins to the head insertablethrough the several slots and provided with grooved portionssubstantially equal to the thicknesses ofthe reins, the'edges beingbeveled outwardly.

6. An underreamer comprising a slotted head having a hollow shank, aspring seated 7 against one end of the hollow portion of the shank, anactuator rod in the shankprojecting below the same and having a springseat against which the other end "of the spring rests, a slotted portionon the actuator rod normally in the shank .but projectable through theshank to receive'a key to hold the sprlng compressed, a slotted end onthe actuator rod,an expander tongue on the head,

cutters havingslotted reins to aline with the slot in theend of theactuator rod and the slot in the-head, and a cross-bar projectablethrough the several slots, the'c'ross-bar having grooves to receive theedges of the slot-s of thereins." I i.

,7; A cross-barf for underreamerscomprisng a substantially rectangularmemberhav ng grooves of progressively increasing depths on opposltefacesf of the member in staggered relation.

on its'side, the widths of the grooves being i 8. A cross-bar forunderreamers comprising a substantially rectangular member havinggrooves of progressively increasing .depthson opposite faces of the'member in staggeredrelation, upwardly extending end projections on'theloar andan intermediate projection spaced from therend projections.

9."A-cross-bar for underreamers comprising a substantially rectangularmember hav-' ing grooves of progressively increasing,

depths on opposite faces of the member in staggered relation, upwardlyextending end projections on the bar and an intermediate projectionspaced from the endprojections, the inner faces of the" end projectionsbeing 7 beveled outwardly. P

rojection spaced from the end projections,

staggered relation, upwardly extending end projections on the bar and anintermediate the inner faces of theend projections being beveledoutwardly, theendsof the bar being i I e beveledto provide pilot; guidesfor inserting the bar throughaislotor slots. Y

I 11. 'An underreamercomprisinga slotted head, a slotted spring:responsive cutter actuator. carried bythe head, cuttershaving slot;

ted reins arranged'in pairs tostraddle the head; a cross-bar insertablethrough the sev eral-slots having grooves on its opposite faces toreceivetheedges of'the groovesof the reins and a cutter expander tongueover which the cutters ride when actuated by the rod to move theircutting portions outwardly.

12. 'An underreamer comprising a slotted head, a slotted springresponsive actuator cararranged in pairs to straddle the'head, a p

ried by the head, cutters having slotted reins cross-bar insertablethrough the several slots having grooves 'on 1ts opposite face toreceive t theedges of the grooves of the reinssthe slot l l in theactuator being longer than the width of the cross-bar and means formovingthe cutters outwardly into cutting position.

aflix my signature.

In testimony whereof I V FRED SWAN.

